A Novel Compact Ultra-Wideband Antenna with Quad Notched Bands Based on S-SCRLHs Resonator

In this paper, a novel compact ultra-wideband (UWB) antenna with a quad band-notched function using S-SCRLHs (splited simplified composite right/left-handed) resonator is presented. The S-SCRLHs resonator, which exhibits quadruple resonance, is realized by coupling double S-SCRLH resonator. Then, the S-SCRLHs resonator is integrated into a UWB antenna consisting of modified circular patch. The proposed UWB antenna operates under the frequency range of 3.0–10.7 GHz. This proposed antenna displays a VSWR < 2(the voltage standing wave ratio) across the entire UWB band and compact dimensions of 25 × 20 mm², which is 0.2λ (free space) at 3.0 GHz. By changing the dimension of S-SCRLHs resonator, the notched frequencies can be adjusted appropriately in four bands of 3.6–3.8 GHz (WiMAX), 4.5–4.9 GHz (C-band), 5.6–6.0 GHz (WLAN), and 7.2–7.6 GHz (X-band). The antenna can be applicable in the UWB receiver systems where the four kinds of interference signals corresponding to the four bands can be suppressed. The gain varies from 2.1 to 4.5 dBi with gain values of −2.8, −2.6, −1.5 and −2.4 dBi at respective four notch frequencies. The radiation efficiency is no less than 84% throughout the operational bandwidth. The proposed antenna achieves omnidirectional radiation patterns while also providing rejection at desired notches.